PWCVIEW(1) say errors

[Xavier xfm]

Hi,

Why PWCVIEW(1) don't work ?:

> su
Password:
casa# pwcview -d /dev/video8
Webcam set to: 320x240 (sif) at 5 fps
libv4l2: error queuing buf 0: Invalid argument
libv4l2: error queuing buf 1: Invalid argument
libv4l2: error queuing buf 2: Invalid argument
libv4l2: error queuing buf 3: Invalid argument
libv4l2: error reading: Device busy
Error reading from webcam: Device busy
casa#

Any idea ?

Thanks.